1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
|
/*
* Copyright (c) 2021, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Format.h>
#include <AK/Types.h>
#include <LibVT/EscapeSequenceParser.h>
#include <LibVT/EscapeSequenceStateMachine.h>
namespace VT {
EscapeSequenceParser::EscapeSequenceParser(EscapeSequenceExecutor& executor)
: m_executor(executor)
, m_state_machine([this](auto action, auto byte) { perform_action(action, byte); })
{
}
EscapeSequenceParser::~EscapeSequenceParser()
{
}
Vector<EscapeSequenceParser::OscParameter> EscapeSequenceParser::osc_parameters() const
{
VERIFY(m_osc_raw.size() >= m_osc_parameter_indexes.last());
Vector<EscapeSequenceParser::OscParameter> params;
size_t prev_idx = 0;
for (auto end_idx : m_osc_parameter_indexes) {
// If the parameter is empty, we take an out of bounds index as the beginning of the Span.
// This should not be a problem as we won't dereference the 0-length Span that's created.
// Using &m_osc_raw[prev_idx] to get the start pointer checks whether we're out of bounds,
// so we would crash.
params.append({ m_osc_raw.data() + prev_idx, end_idx - prev_idx });
prev_idx = end_idx;
}
return params;
}
void EscapeSequenceParser::perform_action(EscapeSequenceStateMachine::Action action, u8 byte)
{
auto advance_utf8 = [&](u8 byte) {
u32 new_code_point = m_code_point;
new_code_point <<= 6;
new_code_point |= byte & 0x3f;
return new_code_point;
};
switch (action) {
case EscapeSequenceStateMachine::Action::_Ignore:
break;
case EscapeSequenceStateMachine::Action::Print:
m_executor.emit_code_point((u32)byte);
break;
case EscapeSequenceStateMachine::Action::PrintUTF8:
m_executor.emit_code_point(advance_utf8(byte));
break;
case EscapeSequenceStateMachine::Action::Execute:
m_executor.execute_control_code(byte);
break;
case EscapeSequenceStateMachine::Action::Hook:
if (m_param_vector.size() == MAX_PARAMETERS)
m_ignoring = true;
else
m_param_vector.append(m_param);
m_executor.dcs_hook(m_param_vector, intermediates(), m_ignoring, byte);
break;
case EscapeSequenceStateMachine::Action::Put:
m_executor.receive_dcs_char(byte);
break;
case EscapeSequenceStateMachine::Action::BeginUTF8:
if ((byte & 0xe0) == 0xc0) {
m_code_point = byte & 0x1f;
} else if ((byte & 0xf0) == 0xe0) {
m_code_point = byte & 0x0f;
} else if ((byte & 0xf8) == 0xf0) {
m_code_point = byte & 0x07;
} else {
dbgln("Invalid character was parsed as UTF-8 initial byte {:02x}", byte);
VERIFY_NOT_REACHED();
}
break;
case EscapeSequenceStateMachine::Action::AdvanceUTF8:
VERIFY((byte & 0xc0) == 0x80);
m_code_point = advance_utf8(byte);
break;
case EscapeSequenceStateMachine::Action::FailUTF8:
m_executor.emit_code_point(U'�');
break;
case EscapeSequenceStateMachine::Action::OscStart:
m_osc_raw.clear();
m_osc_parameter_indexes.clear();
break;
case EscapeSequenceStateMachine::Action::OscPut:
if (byte == ';') {
if (m_osc_parameter_indexes.size() == MAX_OSC_PARAMETERS) {
dbgln("EscapeSequenceParser::perform_action: shenanigans! OSC sequence has too many parameters");
} else {
m_osc_parameter_indexes.append(m_osc_raw.size());
}
} else {
m_osc_raw.append(byte);
}
break;
case EscapeSequenceStateMachine::Action::OscEnd:
if (m_osc_parameter_indexes.size() == MAX_OSC_PARAMETERS) {
dbgln("EscapeSequenceParser::perform_action: shenanigans! OSC sequence has too many parameters");
} else {
m_osc_parameter_indexes.append(m_osc_raw.size());
}
m_executor.execute_osc_sequence(osc_parameters(), byte);
break;
case EscapeSequenceStateMachine::Action::Unhook:
m_executor.execute_dcs_sequence();
break;
case EscapeSequenceStateMachine::Action::CsiDispatch:
if (m_param_vector.size() > MAX_PARAMETERS) {
dbgln("EscapeSequenceParser::perform_action: shenanigans! CSI sequence has too many parameters");
m_ignoring = true;
} else {
m_param_vector.append(m_param);
}
m_executor.execute_csi_sequence(m_param_vector, intermediates(), m_ignoring, byte);
break;
case EscapeSequenceStateMachine::Action::EscDispatch:
m_executor.execute_escape_sequence(intermediates(), m_ignoring, byte);
break;
case EscapeSequenceStateMachine::Action::Collect:
if (m_intermediate_idx == MAX_INTERMEDIATES) {
dbgln("EscapeSequenceParser::perform_action: shenanigans! escape sequence has too many intermediates");
m_ignoring = true;
} else {
m_intermediates[m_intermediate_idx++] = byte;
}
break;
case EscapeSequenceStateMachine::Action::Param:
if (m_param_vector.size() == MAX_PARAMETERS) {
dbgln("EscapeSequenceParser::perform_action: shenanigans! escape sequence has too many parameters");
m_ignoring = true;
} else {
if (byte == ';') {
m_param_vector.append(m_param);
m_param = 0;
} else if (byte == ':') {
dbgln("EscapeSequenceParser::perform_action: subparameters are not yet implemented");
} else {
m_param *= 10;
m_param += (byte - '0');
}
}
break;
case EscapeSequenceStateMachine::Action::Clear:
m_intermediate_idx = 0;
m_ignoring = false;
m_param = 0;
m_param_vector.clear_with_capacity();
break;
}
}
}
|
